Blower not working on 2006 Grand Prix!
Ok, so last weekend, all of a sudden I noticed my blower was not working. So no heat, no defrost! Not good! I've replaced a couple blower motors in the past, so I figure that's what it is. Taking out the blower is pretty easy, other than the fact you have to get in a very awkward position under the dash to get to the blower. And first, I had to pull three pins on the panel right under the dash, (very easy!)
Once I got the access panel off, there are three screws/bolts (they have a hex head, so a nut driver or socket works great,) to take off, then the blower will drop down. There is a connector from the wire harness you will have to remove from the blower as well.
So I took the blower out, and just to test it, I connected two wires to the connector on the blower and touched the other end of the wires to my battery. The blower hummed at full speed, so I guess the blower is fine!
So there is this little module right behind the blower, where the wires come from that were plugged into the blower. That is the blower motor resistor module. In my 2006 Grand Prix, there is a circuit board inside the module. I found out that the module was 99 bucks at the local auto store. Ouch! Well, I certainly did not want to shell out for the part if that was not the problem, so I did a little troubleshooting. on the module, there are connections for Bat, Gnd, sig, M+, and M-. The "sig" is the signal from the instrument panel. as you change the fan speed on the fan speed control, the voltage changes on that pin. So I checked the voltage on that connection with a multimeter, and the voltage was zero volts with the fan turned off, and then the voltage went higher as I turned the knob up for the fan speed. A very small voltage, however. I believe the voltage was less than a volt with the fan speed on max.
To get the harness out of the module, I just pulled on the clip with a special pliers I have, either that, or pry it slightly with a flathead screwdriver, then at the same time, wiggle out the harness.
The module looked to be attached to mounting bosses, and merely heat sealed on to the mounting boss. To remove the module, what worked great for me, is to just take a medium sized flat head screwdriver, pry between the mounting tab, and it will just pop out. Each mounting tab had two holes. Only one was used, for the heat sealed mounting bosses and the other was not used, but I would use the one that is not used for remounting the new one using sheet metal screws.Once you pop out the old one, get under there and put the new one in place. There are two other mounting bosses that will accommodate small sheet metal screws, so use those for remounting the new module. I would use small hex head sheet metal screws. You might have to experiment with sizes.
So once I got my new module in, reattached the harness, remounted the fan and reconnected it, the blower worked like a charm!
